1. Field of the Invention
The present invention relates generally to the field of connectors for electrical cables and more particularly to a cable connector which incorporates insulation displacement terminals.
2. Prior Art
The prior art includes cable connectors shown in German Patents DE 31 50 568 C1 and DE 32 20 006 C1. In these devices, the axially extending recesses are arranged on the insulating part in such a way that the insulation piercing connecting devices are inserted therein lying inward and, in turn, the individual wires of the conductor cable lie pointing outward approximately parallel in the joined position. Contact can therefore be made between the cutting edges of the insulation piercing connecting devices and the individual wires essentially only in the radial direction, and for this purpose the cutting edges on the insulation piercing connecting devices are angled off outward at right angles. Pressing the individual wires of the conductor cable into the respectively associated cutting edge of the relevant insulation piercing connecting device in the radial direction is performed by projecting threads of the union nut, which either project inward more strongly with increasing screwing-on depth (DE 31 50 568 C1) or act on a finger, which is elastically deformable in the radial direction and presses, in turn, on the wires of the conductor cable (DE 32 20 006 C1). Because of the friction which occurs when the union nut is screwed on between the internal thread of the latter and the insulation of the individual wires of the conductor cable, tangential forces are produced which can cause damage to the conductor insulation or deformation of the cutting edges of the insulation piercing connecting devices, as a result of which contact is impaired. In addition, the manipulation during mounting is awkward, because the relatively stiff individual wires of the conductor cable have a tendency to come out of the outwardly open, axially extending recesses of the insulating part. It is true that this applies less in the case of the embodiment with the elastic intermediate fingers between the union nut and the individual wires, but there is still a risk in this device that the elastic fingers will lift out of the recesses in the insulating part as a consequence of the tangential friction forces occurring when the union nut is being screwed on, as a result of which reliable contact is not ensured.
German Patent DE 42 03 455 C1 shows electric plug-in connectors for a multipole terminal, which have a carrier member and a conductor guide element. The carrier member has insulation piercing connecting devices which are inserted, in the joining direction of the two parts, into recesses in the conductor guide element and whose cutting edges are likewise aligned in the joining direction. In the conductor guide element, the individual wires are positioned in obliquely extending feed-through openings such that it is possible to make contact between the cutting edges of the insulation piercing connecting devices and the individual conductor wires in the joining direction. In accordance with the envisaged multiplicity of the individual wires with which contact is to be made, a correspondingly large number of conductor guide shoulders are provided on the conductor guide element, each of which engage per se in a chamber holding the respective insulating piercing connecting device, there likewise being a corresponding multiplicity of these chambers. On the side averted from the carrier member, the conductor guide element has a corresponding multiplicity of insertion openings, it being necessary for an individual wire to be threaded into each of these insertion openings. This results in awkward manipulation. Moreover, it remains an open question as to how the extraordinarily high joining forces can be applied effectively in the case of a multiplicity of given contact points.